OPUS is both a generic event-driven pipeline environment and a set of applications designed to process the spacecraft telemetry at the Space Telescope Science Institute in Baltimore, Maryland. This paper describes those OPUS applications which process the telemetry, validate the integrity of the information, and produce standard FITS (Flexible Image Transport System) data files for further analysis. The applications are to a great extent table-driven in an effort to reduce code changes, improve maintainability, and reduce the difficulty of porting the system. The tables which drive the applications are explained in some detail to illustrate how future missions can take advantage of the OPUS systems.